The War for the Oc'thylliha
Theselorius, an early demon king. His law - do the fuck you want. Pillage rape eat souls whatever demons are number one and all that. Mortals were not into that for obvious reasons. They united and drove them off. So the demons find this gate. This sort of tear in space and on the other side of it they find this new world of existence. And by tapping into its power they get crazy strong. But in doing this they awoke the Forgotten. The originals inhabitants of that world. They were not fond of the demons and their power draining shenanigans. They want the demons to leave. Demons don’t want to leave. So they started a war for the who could stay in this world (The Oc'thyllia). Fucked up time space they did. Cosmic level battle ensues. Goes on for a fucking long ass time. 68 demon kings rise and fall in this time. This goes on for a while until Ishlahar takes the crown with his lieutenant Plagorias. They’re a real team these two. Ishlahar is brash and passionate and Plagorias is cunning and calculating. They get the demons closer to winning than any kind before Ishlahar could do on their own. So the king of the Forgotten, Azuria, reckons he’s gotta put a button on this and quick. (Also side note Azuria has outlasted 68 of the demon kings in this war. He’s kind of a big deal and was basically just fucking with the demons until Ishlahar and Plagorias actually became a credible threat.) So he creates a lame as fuck copy of the world they’ve been fighting over, called The Cauldron and he pushes all the demons into it. Risky move for Azuria by the way who could have died using all that power. This place was so twisted and poorly made that most of the demons lost their minds or died there. Their "Footprints" are the current inhabitants of The Cauldron. They are the remnants of the demons that “survived” there. They’re essentially just this floating consciousness of madness and fire and sad times. (Another side note. One day way in the future a bit of the footprints essence leaks out of the Cauldron and into the northern wind and merges with Clay Willons's soul after he gets lost in the North. But that’s a whole other story.) Three demons of the Theselorian era survive the war. Ishlahar survives the "trip" to The Cauldron. His will and power are strong enough that he survives. Plagorias is ripped into a million pieces, joining the tempest of souls left behind in the Couldron. Gailith is the second, who moments before the conclusion of the war escapes (see her character bio for more). Third guy, Neeran Iatai Nareen. He escaped to a strange, parallel universe where the souls of everyone after their death come to rest (Mycc'terehq) very early in the war. One of the very few corners of the universe that the war never touched. Super powerful little shit this one is he fucking lived in the plane of death for millions of years. After the war ended, Ishlahar started a new race of demons. It’s not so much a race as a "career". With a code outlined by Plagorias before he died near the end of the war. If you wanna take peoples souls you gotta be cool about it. Because last time they did it without permission and that didn’t work out so well. So people have to want it. So the new demons offer miracles and favors in exchange for the souls of willing mortals. Also Ishlahar became the god of darkness sometime after he established the Plagorian age.